Objective, novel, and cost-effective approaches for assessing and improving patient adherence to treatment are in high demand. Of particular interest are methods for quantifying the patient's adherence to (and preference for) wearing therapeutic and prescribed footwear and offloading devices (collectively, “therapeutic footwear.”) An exemplary use of such technology is for monitoring diabetic patients who have developed neuropathic foot ulcers and who must wear therapeutic footwear as the most important part of their healing regimen. In the field of diabetic foot ulcer prevention, knowledge of patient preference for specific types of footwear will aid developers improve the design of customized footwear, thus improving healing
Patient adherence to wearing their therapeutic footwear can significantly enhance and improve healing. Although laboratory studies using total contact insoles and rocker-sole shoes have demonstrated modest reductions in pressure, these clinical footwear trials are inconclusive. Within 12 months, 26-42% of the studied patients had re-ulcerated. These results are likely due to lack of patient adherence to footwear. For example, despite taking a significant number portion of their daily steps at home (some studies have estimated this fraction to be over 50%), patients view their homes as “safe zone” where they typically do not wear prescribed footwear. As a result, high-risk patients wear their therapeutic footwear not as often as they should (some studies estimate that such patients wear the required footwear only 15-28% of the time).
What exacerbates the problem faced by such patients is that the methods used studies quantify patient adherence likely underestimate the patients' non-adherence to a significant degree. Adherence is typically measured through face-to-face interviews with a small number of patients. Previous investigations have shown that patients under-report “sensitive” conditions in face-to-face interviews versus telephone or paper surveys.
The present invention consists of a system for monitoring, assessing and improving patient adherence to any prescribed footwear.
Applied to diabetic care, the present invention can monitor patient adherence to instructions provided by caregivers—specifically for using a cast boot or other prescribed offloading devices and therapeutic footwear during walking, and/or foot loading condition. The invention can also remind and/or alert the patient if he or she forgets or neglects to use the prescribed footwear during standing and walking or other predefined movements. The invented system can promote the use of therapeutic footwear, socks or removable cast walkers (RCWs).
Foot ulceration is one of the most common precursors to lower extremity amputations among diabetics [3-5]. Ulcerations are pivotal events in limb loss for two important reasons: they provide a direct pathway for infection [6] and also cause progressive tissue necrosis and poor wound healing in the presence of ischemia. In diabetic adults, foot infections rarely develop in the absence of a wound. In this population, ulcers are the most common type of wound [6]. Foot ulcer, therefore, plays a central role in the causal pathway to lower extremity amputation [7].
Clearly, an effective treatment of foot ulcerations is critical to any plan for amputation prevention. Lowering of pressure, shear, and repetitive injury to the sole of the foot are fundamental to diabetic ulcer care.
Total Contact Casting (TCC) is considered the “ideal” gold standard to heal diabetic foot ulcers [8-12]. TCCs have been shown to reduce pressure at the site of ulceration by 84-92% [13]. Despite a significant body of clinical and laboratory work indicating their efficacy and safety, total contact casts are not widely used due to several practical barriers limiting their adoption by the general medical community. They are difficult to apply, expensive, and place significant demands on resources from busy clinics. Additionally, should the foot ulcer require re-examination, the TCC must be removed and then fully reapplied. Due to these disadvantages, an effective alternative to TCCs is needed.